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| author | coreyg <coreyg@13f79535-47bb-0310-9956-ffa450edef68> | 2014-11-21 09:30:19 +0000 |
|---|---|---|
| committer | coreyg <coreyg@13f79535-47bb-0310-9956-ffa450edef68> | 2014-11-21 09:30:19 +0000 |
| commit | 200a40b332420f94992eb39a6d0ea1cf1490ffc4 (patch) | |
| tree | 1c76ef1d254c7bfc91128a313d319bd60da9d01e /site/trunk/site-publish/rdb-das-transaction-control.html | |
| parent | 85f53ab6ab4f664d63774c94b672a875c9e52b8a (diff) | |
Adding tuscany's website to their svn repo for svnpubsub
git-svn-id: http://svn.us.apache.org/repos/asf/tuscany@1640879 13f79535-47bb-0310-9956-ffa450edef68
Diffstat (limited to 'site/trunk/site-publish/rdb-das-transaction-control.html')
| -rw-r--r-- | site/trunk/site-publish/rdb-das-transaction-control.html | 268 |
1 files changed, 268 insertions, 0 deletions
diff --git a/site/trunk/site-publish/rdb-das-transaction-control.html b/site/trunk/site-publish/rdb-das-transaction-control.html new file mode 100644 index 0000000000..26c0a65abd --- /dev/null +++ b/site/trunk/site-publish/rdb-das-transaction-control.html @@ -0,0 +1,268 @@ + +<!-- + + Licensed to the Apache Software Foundation (ASF) under one or more + contributor license agreements. See the NOTICE file distributed with + this work for additional information regarding copyright ownership. + The ASF licenses this file to You under the Apache License, Version 2.0 + (the "License"); you may not use this file except in compliance with + the License. You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE- 2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. +--> + + +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<HTML> + <HEAD> + <!-- generateKeywords macro --> + <META name="description" content="Apache Tuscany"> + <META name="keywords" content="apache, apache tuscany, tuscany, service, services, fabric, soa, service oriented architecture, sca, service component architecture, das, sdo, csa, ruby, opensource"> + <!-- generateKeywords macro end --> + + <LINK type="text/css" rel="stylesheet" href="http://tuscany.apache.org/stylesheets/default.css"> + <LINK rel="SHORTCUT ICON" href="https://cwiki.apache.org/confluence/display/TUSCANY/$images/favicon.ico"> + <TITLE>Apache Tuscany : RDB DAS - Transaction Control</TITLE> + <META http-equiv="Content-Type" content="text/html;charset=UTF-8"></HEAD> + + <BODY onload="init()"> + <!-- topNav macro --> + <TABLE valign="top" border="0" cellspacing="0" cellpadding="0" width="100%" background="http://tuscany.apache.org/images/TuscanyLogoNEW_Text_120px_bg.jpg"> + <TR> + <TD valing="top" align="left"> + <A href="https://cwiki.apache.org/confluence/pages/viewpage.action?spaceKey=TUSCANY&title=$siteroot"><IMG src="http://tuscany.apache.org/images/TuscanyLogoNEW_Text_120px_bg.jpg" height="91" width="25" border="0"></A> + </TD> + <TD> + <A href="http://tuscany.apache.org/"><IMG src="http://tuscany.apache.org/images/TuscanyLogo.jpg" border="0"></A> + </TD> + + <TD width="100%"> + + </TD> + + <!-- Adds the edit page link to the top banner--> + <TD valign="bottom"> + <DIV style="padding: 2px 10px; margin: 0px;"> + <A href="https://cwiki.apache.org/confluence/pages/editpage.action?pageId=66405"> + <IMG src="http://tuscany.apache.org/images/notep_16.gif" height="16" width="16" border="0" align="absmiddle" title="Edit Page"></A> + </DIV> + </TD> + + </TR> + </TABLE> + <!-- topNav macro end --> + + <!-- breadCrumbs macro --> + <TABLE border="0" cellpadding="2" cellspacing="0" width="100%"> + <TR class="topBar"> + <TD align="left" valign="middle" class="topBarDiv" nowrap="true" width="100%"> + <A href="home.html" title="Apache Tuscany">Apache Tuscany</A> > <A href="home.html" title="Home">Home</A> > <A href="das-overview.html" title="DAS Overview">DAS Overview</A> > <A href="das-java.html" title="DAS Java">DAS Java</A> > <A href="das-java-documentation-menu.html" title="DAS Java Documentation Menu">DAS Java Documentation Menu</A> > <A href="" title="RDB DAS - Transaction Control">RDB DAS - Transaction Control</A> + </TD> + + <TD align="right" valign="middle" class="topBarDiv" align="left" nowrap="true"> + <A href="http://mail-archives.apache.org/mod_mbox/tuscany-user">User List</A> | <A href="http://mail-archives.apache.org/mod_mbox/tuscany-dev">Dev List</A> | <A href="http://issues.apache.org/jira/browse/Tuscany">Issue Tracker</A> + </TD> + </TR> + </TABLE> + <!-- breadCrumbs macro end --> + + + <TABLE border="0" cellpadding="0" width="100%" bgcolor="#FFFFFF"> + <TR> + <TD align="left" valign="top"> + + <!-- pageContent macro --> + <DIV id="PageContent"> + + <DIV class="pagecontent"> + <DIV class="wiki-content"> + <TABLE class="sectionMacro" border="0" cellpadding="5" cellspacing="0" width="100%"><TBODY><TR> +<TD class="confluenceTd" valign="top" width="15%"> +<DIV class="panel" style="background-color: #ECF4D1;border-color: #C3CDA1;border-style: solid;border-width: 1px;"><DIV class="panelHeader" style="border-bottom-width: 1px;border-bottom-style: solid;border-bottom-color: #C3CDA1;background-color: #C3CDA1;"><B>General</B></DIV><DIV class="panelContent" style="background-color: #ECF4D1;"> +<P><A href="home.html" title="Home">Home</A><BR> +<A href="http://www.apache.org/licenses/LICENSE-2.0.html" class="external-link" rel="nofollow">License </A><BR> +<A href="das-java-get-involved.html" title="DAS Java Get Involved">Get Involved</A><BR> +<A href="das-java-found-a-bug.html" title="DAS Java Found A Bug">Found a Bug?</A></P> +</DIV></DIV> +<DIV class="panel" style="background-color: #ECF4D1;border-color: #b4b4b5;border-style: solid;border-width: 1px;"><DIV class="panelHeader" style="border-bottom-width: 1px;border-bottom-style: solid;border-bottom-color: #b4b4b5;background-color: #C3CDA1;"><B>DAS Java</B></DIV><DIV class="panelContent" style="background-color: #ECF4D1;"> +<P><A href="das-java.html" title="DAS Java">DAS Java Home</A><BR> +<A href="das-java-faq.html" title="DAS Java - FAQ">FAQ</A><BR> +<A href="das-java-releases.html" title="DAS Java Releases">Downloads</A><BR> +<A href="das-java-documentation-menu.html" title="DAS Java Documentation Menu">Documentation</A><BR> +<A href="https://svn.apache.org/repos/asf/tuscany/java/das/" class="external-link" rel="nofollow">Source Code</A></P> +</DIV></DIV></TD> +<TD class="confluenceTd" valign="top" width="85%"> +<DIV class="panel" style="background-color: #ffffff;border-color: #ECF4D1;border-style: solid;border-width: 1px;"><DIV class="panelHeader" style="border-bottom-width: 1px;border-bottom-style: solid;border-bottom-color: #ECF4D1;background-color: #ECF4D1;"><B>Transaction Management in RDB-Data Access Service (RDB DAS)</B></DIV><DIV class="panelContent" style="background-color: #ffffff;"> +<UL> + <LI><A href="#RDBDAS-TransactionControl-Overview">Overview</A></LI> + <LI><A href="#RDBDAS-TransactionControl-DASmanagedtransactions">DAS managed transactions</A></LI> + <LI><A href="#RDBDAS-TransactionControl-Externallymanagedtransactions">Externally managed transactions</A></LI> +</UL> +</DIV></DIV> + +<H3><A name="RDBDAS-TransactionControl-Overview"></A><A name="RDBDAS-TransactionControl-Overview"></A>Overview</H3> + +<P>A typical enterprise application accesses and stores information in one or more databases. Data integrity is <BR> +the most essential aspect of correct business functioning. Transactions control the concurrent access of data <BR> +by multiple programs. In the event of a system failure, transactions make sure that after recovery the data will<BR> + be in a consistent state. This document helps to understand transaction management in RDB DAS.</P> + +<P>One DAS instance is always associated with one database and one Connection. DAS participates in <BR> +<B>A> DAS managed and B> Externally managed transactions</B>.</P> + +<H3><A name="RDBDAS-TransactionControl-DASmanagedtransactions"></A><A name="RDBDAS-TransactionControl-DASmanagedtransactions"></A>DAS managed transactions</H3> + +<P>By default, the RDB DAS assumes responsibility for managing transaction boundaries by executing commit and <BR> +rollback operations against the database. A configuration attribute managedtx is assumed with default value <BR> +TRUE. This signals DAS to control the transaction. The boundaries of these transactions are as follows:</P> + +<P><B>Reading Data</B><BR> +Queries to the database are always made by calling DAS command's "executeQuery()" method. The associated <BR> +transaction lives for the duration of this method execution. That is, the transaction can be thought to start <BR> +when control is transferred to "executeQuery" and the transaction ends just prior to return from this method.</P> + +<P><B>Writing Data</B><BR> +Writes can be accomplished by two DAS APIs. First is calling the DAS "execute()" command against a command the <BR> +will perform write operations and, in this case, the transaction boundaries are the same as read queries. That <BR> +is the transaction life matches the life of the "execute" processing. If the method returns without exception <BR> +then the application can assume that any changes were successfully committed to the database. If an exception is <BR> +returned then the changes will have all been rolled back.</P> + +<P>The second API used by clients is the DAS applyChanges() method (see ChangeSummaryProcessing). Again, the <BR> +boundaries of the transaction match the boundaries of the call to the method. The DAS will create a set of <BR> +INSERT/UPDATE and DELETE statements to flush the graph changes to the database and all of these statements <BR> +will be executed as part of a single transaction. If the method returns without exception then the application <BR> +can assume that all changes were successfully committed to the database. If an exception is returned then the changes <BR> +will have all been rolled back.</P> + +<P><B>Use</B></P> + +<P>This mode is useful for simple data operations, where there is no need of having group of SQL statements or group of DAS <BR> +Commands in one transaction unit. At the maximum one applyChanges() call having multiple INSERT/UPDATE/DELETE executes <BR> +under one transaction. Cases where multiple applyChanges() method calls or multiple executeQuery() method calls are <BR> +required to be part of one transaction, this mode is not useful. In this mode, the database Connection can be internally <BR> +obtained using DAS Config ConnectionInfo settings or database Connection can also be passed from the client to DAS instance. <BR> +When DAS obtains database Connection internally, in Config ConnectionInfo, settings can either specify DataSource name or <BR> +Database Driver related information. Typical examples - </P> +<UL> + <LI>When using Tomcat based web app with DAS, Tomcat configured DataSource name is set in the DAS Config.</LI> + <LI>When using J2SE application client with DAS, Database Driver related information from DAS Config is used to form a database Connection.</LI> +</UL> + + +<P>When multiple SQL statements/DAS commands need to be part of one transaction and also when multiple DAS instances need to participate <BR> +in one transaction, the other mode "Externally managed transactions" is useful.</P> + +<H3><A name="RDBDAS-TransactionControl-Externallymanagedtransactions"></A><A name="RDBDAS-TransactionControl-Externallymanagedtransactions"></A>Externally managed transactions</H3> + +<P>The RDB DAS provides a straightforward mechanism for working with external transactions. In this mode, DAS is configured to not issue <BR> +commit/rollback. This behavior is needed to have the DAS participate in a larger transaction since some external party is responsible <BR> +for these actions. </P> + +<P><B>Use</B></P> + +<P>The scope of transaction support is a blend of <B>Supports</B> and <B>Mandatory</B> transaction attributes in J2EE scenario. i.e. DAS will use the <BR> +client's transaction if it is available. DAS does not throw exception if external client transaction is not available, but the end result <BR> +without external transaction is unpredictable. So, when using DAS in this mode, client needs to ensure availability of external transaction <BR> +encompassing required DAS/s commands. External transaction can be JDBC transaction or JTA transaction. </P> + +<P>When JDBC transaction, it is possible to group multiple Commands from single DAS instance in one transaction. Also nested transactions using <BR> +multiple DAS instances can be carried out. AS JTA does not support nested transactions, if <B>nested transactions</B> is the requirement, JDBC <BR> +Transactions should be used. For example:-</P> + +<DIV class="preformatted panel" style="border-width: 1px;"><DIV class="preformattedContent panelContent"> +<PRE>Das1 = DAS.FACTORY.createDAS(jdbcconn1); +Das2 = DAS.FACTORY.createDAS(jdbcconn2); + +try { + doSomeDAS1Stuff(); + doSomeDAS2Stuff(); + jdbcconn2.commit(); + doSomeDAS1Stuff(); + jdbcconn1.commit(); +} catch (AnyException ex) { + jdbcconn1.rollback(); + jdbcconn2.rollback(); +} +</PRE> +</DIV></DIV> + +<P>When JTA transaction, multiple units like JMS, DAS1(derbydatabase1), DAS2(derbydatabase2/mysqldatabase2) can be part of single transaction. <BR> +See example:-</P> + +<DIV class="preformatted panel" style="border-width: 1px;"><DIV class="preformattedContent panelContent"> +<PRE>tx.begin(); +try { + doSomeJMSStuff(); + doSomeDAS1Stuff(); + doSomeDAS2Stuff(); + tx.commit(); +} catch (AnyException ex) { + tx.rollback(); +} +</PRE> +</DIV></DIV> + +<P>In both the examples above, the DAS1 and DAS2 have been configured to not manage transactions since this is handled by the calling program.<BR> +The DAS is set to behave this way by a piece of configuration (typically via a configuration xml file). The following config file snippet <BR> +illustrates this setting:</P> + +<DIV class="preformatted panel" style="border-width: 1px;"><DIV class="preformattedContent panelContent"> +<PRE><Config xsi:noNamespaceSchemaLocation="http:///org.apache.tuscany.das.rdb/config.xsd" + xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> + + <ConnectionInfo managedtx="false"/> + +</Config> +</PRE> +</DIV></DIV> + +<P><B>Note</B> When using DAS with "Externally managed transactions", it is required by the client to pass appropriate Connection object to DAS <BR> +instance. There is no meaning to forming Connection internally in DAS using Config info, as such Connections will not be part of external <BR> +Transaction Control.</P> + +<P><B>Methods Not Used in Externally managed transactions</B><BR> +DAS does not invoke any method that might interfere with the transaction boundaries set by the Transaction Manager. The list of prohibited <BR> +methods follows: </P> +<UL> + <LI>The commit, setAutoCommit, and rollback methods of java.sql.Connection</LI> + <LI>The getUserTransaction method of javax.ejb.EJBContext</LI> + <LI>Any method of javax.transaction.UserTransaction</LI> +</UL> + + +<P><B>Note</B> DAS never allows AutoCommit(TRUE) for the Connection it is using and throws Exception if this mode is detected.</P> +</TD></TR></TBODY></TABLE> + </DIV> + </DIV> + </DIV> + <!-- pageContent macro end --> + + </TD> + </TR> + </TABLE> + + <!-- footer macro --> + <SCRIPT src="http://www.google-analytics.com/urchin.js" type="text/javascript"> + </SCRIPT> + <SCRIPT type="text/javascript"> + _uacct = "UA-1174707-5"; + urchinTracker(); + </SCRIPT> + + <A href="http://www.statcounter.com/" target="_blank"><IMG src="http://c26.statcounter.com/counter.php?sc_project=2619156&java=0&security=94bd7e7d&invisible=0" alt="website stats" border="0"></A> + + <DIV class="footer"> + Copyright � 2003-2012, The Apache Software Foundation </BR> + Apache Tuscany and the Apache Tuscany project logo are trademarks of The Apache Software Foundation. + </DIV> + <!-- footer macro end --> + + </BODY> +</HTML> |